Updated

Top Republican senators on Monday sharply criticized Democratic Sen. Dianne Feinstein for waiting nearly two months to inform the Judicary Committee about the decades-old sexual assault allegations now upending Supreme Court nominee Brett Kavanaugh's confirmation, calling the delay "deeply disturbing" even as they agreed with the White House that the accuser deserves to be heard.

That accuser, Christine Blasey Ford, sent Feinstein's office a letter in July, according to The Washington Post. But Feinstein only went public with the then-anonymous claim last Thursday, after a report by The Intercept indicated she was "withholding" a key document about Kavanaugh and just one week before a now-postponed, crucial Judiciary Committee vote on his confirmation.

In a dramatic, full-throated speech on the Senate floor, Senate Majority Leader Mitch McConnell, R-Ky., excoriated Democrats for what he described as "11th hour" theatrics, saying the accusations should have been raised earlier either in "the thousand-plus follow-up questions that senators sent to Judge Kavanaugh in writing," or the closed, off-the-record session held by the Judiciary Committee.

“Now, an accusation of 36-year-old misconduct dating back to high school has been brought forward at the last minute in an irregular manner,” McConnell said. “It is an accusation which the ranking member of the committee of jurisdiction has known about for at least six weeks -- known about for six weeks -- yet chose to keep secret until the 11th hour.”

McConnell also accused Democrats of deliberately orchestrating the leak of the letter's existence ahead of The Intercept's report. "The chain of custody of this letter runs through the Democratic side of the Judiciary Committee," he said.

McConnell, who concluded the situation was "really not fair" to either Kavanuagh or Ford, was one of several Republicans who unloaded on Democrats throughout the day.

"The Minority withheld even the anonymous allegations for six weeks, only to later decide that they were serious enough to investigate on the eve of the committee vote, after the vetting process had been completed," Judiciary Committee Chairman Chuck Grassley, R-Iowa, said in a statement, which also noted that "Dr. Ford deserves to be heard."

Grassley slammed Feinstein for not telling Republicans, even privately, about the claims against Kavanaugh during days of private and public hearings on the nominee. Ford has claimed that during a summer in the 1980s, when they both were in high school, Kavanaugh forced himself on her and covered her mouth with his hand before she escaped.

FOUR WAYS DEMOCRATS' PLAN TO DERAIL KAVANAUGH COULD BACKFIRE

"Unfortunately, committee Republicans have only known this person's identity from news reports for less than 24 hours and known about her allegations for less than a week," Grassley continued. "Senator Feinstein, on the other hand, has had this information for many weeks and deprived her colleagues of the information necessary to do our jobs."

The top Republican also accused Feinstein of refusing to help set up follow-up calls involving Kavanaugh and Ford, which he called "standard procedure" when there are updates to a nominee's background file.

"I asked Senator Feinstein’s office yesterday to join me in scheduling these follow-ups," Grassley wrote. "Thus far, they have refused. But as a necessary step in evaluating these claims, I’ll continue working to set them up."

In response, all ten Democrats on the Judiciary Committee issued  a statement condemning Republicans for holding staff-level calls with Kavanaugh in the wake of the allegations, saying the FBI should investigate first.

"It is really not fair to either of them the way it is was handled.”

— Maine Republican Sen. Susan Collins

“In view of the enormity and seriousness of these allegations, a staff-only phone call behind closed doors is unacceptable and Democratic staff will not participate," the senators wrote. "This isn’t how things should be done and is in complete violation of how this committee has worked in the past."

Fox News has learned that the FBI would ordinarily require specific instructions from the White House to further review the allegations, which do not involve a federal crime within the applicable statute of limitations.

Meanwhile, another key member of the Judiciary Commitee, Sen. Orrin Hatch, R-Utah, agreed that "any accuser deserves to be heard." But he also intimated that Feinstein had, at best, badly botched the situation.

WHO IS CHRISTINE BLASEY FORD, THE WOMAN WHO ACCUSED KAVANUAGH OF SEXUAL ASSAULT?

"I remain deeply disappointed by the way Senate Democrats have so grossly mishandled these accusations thus far," Hatch said. "It seems in bad faith to hold this information from Republicans and from the FBI for over a month and then to suggest at the final hour that the only path forward is delaying the confirmation to allow the FBI to investigate."

Hatch spoke with Kavanaugh in the wake of Ford's allegations, and said that the nominee told Hatch he was not at a party like the one she describes, and that Ford may be "mistaking" him for someone else, Fox News has learned. In the Washington Post's story outlining Ford's accusations, she acknowledges she could not recall who owned the house where the alleged assault occured, or why  the teens were gathered there.

Ford provided The Post with documentation that showed she had told her therapist in 2012 that four individuals "from an elitist boys’ school" who are now "highly respected and high-ranking members of society in Washington" had attacked her decades earlier. But she did not mention Kavanaugh by name at that time, and told The Post that the therapist had misunderstood her by saying she was attacked by four people, rather than Kavanaugh and his friend.

A key potential swing vote, Maine Republican Sen. Susan Collins, told reporters Monday, "Obviously if Judge Kavanaugh has lied about what happened, that would be disqualifying."

But, she added, "There are an awful lot of questions, inconsistencies, gaps, and that's why to be fair to both, we need to know what happened. ...  I want to have both individuals come before the Senate Judiciary Committee and testify under oath."

Late Sunday, Collins said in an interview with The New York Times that the Democrats had treated both Kavanaugh and his accuser unfairly -- remarks that McConnell quoted Monday.

“What is puzzling to me is the Democrats, by not bringing this out earlier, after having had this information for more than six weeks, have managed to cast a cloud of doubt on both the professor and the judge,” Collins told the paper. “If they believed Professor Ford, why didn’t they surface this information earlier so that he could be questioned about it? And if they didn’t believe her and chose to withhold the information, why did they decide at the 11th hour to release it? It is really not fair to either of them the way it is was handled.”

In a statement, Sen. John Cornyn, R-Texas, similarly took aim at Feinstein: "That Democrats have so egregiously mishandled this up until now is no excuse for us to do the same. If Democrats reject the committee handling this swiftly and in a bipartisan way through regular order, then it’s clear that their only intention is to smear Judge Kavanaugh and derail his nomination.”

LAWYER FOR KAVANAUGH ACCUSER DOWNPLAYED SEX ASSAULT ACCUSATIONS AGAINST CLINTON, FRANKEN

The Judiciary Committee vote, once scheduled for Thursday, on whether to advance Kavanaugh's nomination has been postponed, and a hearing has been scheduled at which both Kavanaugh and Ford are expected to testify.

The Committee has 11 Republicans and 10 Democrats, and one of the Republicans -- Arizona Sen. Jeff Flake -- indicated he wanted more information on Ford's claims before a vote is held.

It is not strictly necessary for a nominee to be approved by the Committee in order to be confirmed by the full Senate. In 1991, Clarence Thomas narrowly won Supreme Court confirmation after the Judiciary Committee sent his nomination to the Democrat-held Senate floor without a recommendation, in the wake of sexual harassment allegations by Anita Hill that he strenuously denied.

But as the day progressed, Republicans increasingly seemed open to holding off on the key vote.  President Trump on Monday told reporters that the Senate should "hear everybody out" in a "full process," even as he praised Kavanaugh as "one of the finest people that I've ever known" and called Democrats' late release of the accusation "very unfortunate."

"If it takes a little delay, it'll take a little delay," Trump said in the White House.

Earlier in the day, top Trump aide Kellyanne Conway had said that the accuser "should not be ignored or insulted" and instead should "be heard."

Anti-Kavanaugh sentiment, which led to dozens of demonstrations and arrests during his confirmation hearings earlier this month, was poised to spill out onto the streets on Monday. Planned Parenthood announced its intention to hold a rally outside the Supreme Court in the evening in support of Ford and "to demand that senators immediately stop Kavanaugh's nomination."

The timeline is expected to become a central issue in the coming days. Ford had contacted The Washington Post through a tip line in "early July" about the alleged episode, according to the paper, and also corresponded with her local congresswoman, Rep. Anna Eshoo, D-Calif. at approximately the same time.

At that point, The Post reported, Kavanaugh was widely discussed as a potential Supreme Court pick, but President Trump had not yet announced his selection -- meaning these correspondences occured sometime before July 9.

Feinstein, the ranking Democrat on the Judiciary Committee, then received a letter dated July 30, 2018 from Ford, who wrote that Kavanaugh had pinned her to a bed and covered her mouth in the early 1980s. But the top Democrat was publicly mum about those accusations until last Thursday, when she released a cryptic statement saying that she had received information from an individual who "strongly requested confidentiality" and had "referred the matter to federal investigative authorities."

The Intercept published a story the day before, which indicated that the letter had become something of an open secret on Capitol Hill -- but that Feinstein had refused to share it with other members of the Judiciary Committee. The report did not specify who leaked the information in the letter, but claimed that Feinstein's actions had caused tension on the Judiciary Committee.

Fox News' Chad Pergram contributed to this report.